1. Technical Field
The present invention relates to a spindle motor, more particularly, to an inner rotor type spindle motor which is required to be thinner, and to a recording disk drive having the spindle motor.
2. Description of the Related Art
In recent years, signal recording/reproducing devices such as hard disk drives (HDDs, hereinafter) are incorporated in portable devices such as cell phones, and this tendency accelerates size and thickness reductions of HDDs from year to year. In addition, when the signal recording/reproducing devices such as hard disk drives are incorporated in the portable devices, as compared with a conventional case where they are incorporated in personal computers, it is required to largely enhance a resistance against an external impact such as a drop impact. In correspondence with these requirements of the HDD, a spindle motor to be incorporated in the HDD is also increasingly required to reduce its size and thickness and to enhance the impact resistance. To meet the requirements, types of spindle motors are moving to an inner rotor type spindle motor in which a stationary member surrounds a rotor and a fluid dynamic pressure bearing utilizing dynamic pressure generated by fluid.
A conventional structure will be described later herein with reference to FIG. 5A by way of contrast with an embodiment of the present invention. Generally, however, according to this inner rotor type spindle motor, although the impact resistance around the bearing can be enhanced, the enhancement of the impact resistance against the mounting manner of other portions, especially a flexible printed circuits (FPC, hereinafter) is not yet sufficient. For example, it is necessary to install wires from inside to outside of a base using the FPC for supplying power, but since it is necessary to install the wire in a narrow space, a FPC disposed on a stator is bent at a sharp angle and fixed on a lower surface of the base when the FPC passes through a through hole of the base. If the FPC is strongly bent, the FPC exhibits a great resilience for returning the FPC to its original state, a force for always separating the base is strongly applied to a lower surface of the base that is a mounting location of the outside of the base. Therefore, when an external impact is applied when a portable device falls, there is a high risk that the FPC is easily peeled off from the base and a contact failure occurs between an external power supply and an external connect portion formed on a lower surface of the base of the FPC. It can also be contemplate to incline a hole so that a wire can be installed easily, but it is difficult to form a hole which is inclined with respect to a small base, and there is a drawback that the cost is increased correspondingly.